共查询到20条相似文献，搜索用时 93 毫秒
1.
Road markings are used to provide guidance and instruction to road users for safe and comfortable driving. Enabling rapid, cost-effective and comprehensive approaches to the maintenance of route networks can be greatly improved with detailed information about location, dimension and condition of road markings. Mobile Laser Scanning (MLS) systems provide new opportunities in terms of collecting and processing this information. Laser scanning systems enable multiple attributes of the illuminated target to be recorded including intensity data. The recorded intensity data can be used to distinguish the road markings from other road surface elements due to their higher retro-reflective property. In this paper, we present an automated algorithm for extracting road markings from MLS data. We describe a robust and automated way of applying a range dependent thresholding function to the intensity values to extract road markings. We make novel use of binary morphological operations and generic knowledge of the dimensions of road markings to complete their shapes and remove other road surface elements introduced through the use of thresholding. We present a detailed analysis of the most applicable values required for the input parameters involved in our algorithm. We tested our algorithm on different road sections consisting of multiple distinct types of road markings. The successful extraction of these road markings demonstrates the effectiveness of our algorithm. 相似文献
2.
A mobile laser scanning (MLS) system allows direct collection of accurate 3D point information in unprecedented detail at highway speeds and at less than traditional survey costs, which serves the fast growing demands of transportation-related road surveying including road surface geometry and road environment. As one type of road feature in traffic management systems, road markings on paved roadways have important functions in providing guidance and information to drivers and pedestrians. This paper presents a stepwise procedure to recognize road markings from MLS point clouds. To improve computational efficiency, we first propose a curb-based method for road surface extraction. This method first partitions the raw MLS data into a set of profiles according to vehicle trajectory data, and then extracts small height jumps caused by curbs in the profiles via slope and elevation-difference thresholds. Next, points belonging to the extracted road surface are interpolated into a geo-referenced intensity image using an extended inverse-distance-weighted (IDW) approach. Finally, we dynamically segment the geo-referenced intensity image into road-marking candidates with multiple thresholds that correspond to different ranges determined by point-density appropriate normality. A morphological closing operation with a linear structuring element is finally used to refine the road-marking candidates by removing noise and improving completeness. This road-marking extraction algorithm is comprehensively discussed in the analysis of parameter sensitivity and overall performance. An experimental study performed on a set of road markings with ground-truth shows that the proposed algorithm provides a promising solution to the road-marking extraction from MLS data. 相似文献
3.
提出了一种从车载激光扫描数据中自动提取路面的方法。通过分析车载激光扫描点云的空间特征,提出运用近似平面约束法、有序最小二乘坡度估计法和多尺度窗口迭代分析法进行初始路面种子点提取;然后基于局部坡度滤波方法提取所有的路面点;最后选择两组实际点云数据进行实验。结果表明,该方法能快速准确地提取高速公路路面点云,实验数据的提取准确率为95.74%,完整率为98.11%。 相似文献
4.
《International Journal of Digital Earth》2013,6(6):432-449
As a state-of-the-art mapping technology, mobile laser scanning (MLS) is increasingly applied to fields such as digital presentations of city environments. However, its application has recently met a bottleneck in data processing. It has been found that conventional methods for geometrically modeling 3D scattered points are inadequate when dealing with large volumes of MLS data. In fact, this is a challenge that has already been noted in the MLS-relevant fields, e.g. remote sensing, robot perception, and pattern recognition. A variety of algorithms under the schematic frame of analysis, modeling and synthesis (AMS) have been developed in these fields. The AMS paradigm is to first extract the implicit geometric primitives within each scan profile by geometrically modeling its 2D scattered points (GM2P). The resultant 2D geometric primitives are then integrated to restore the real 3D geometrical models. In this process, GM2P is a kernel procedure whereby a review of the GM2P algorithms is assumed to be of significance for developing new efficient algorithms for geometrically modeling 3D scattered points. This idea is supported by MLS sampling often being executed via parallel scan profiles. Indeed, the results of the literature review indicate an avenue for methodologically improving MLS in data processing. 相似文献
5.
车载激光扫描数据中实线型交通标线提取 总被引：1，自引：1，他引：0
本文提出一种基于路面点云强度增强的车载激光点云实线型交通标线提取方法。首先通过预处理提取路面点云，获取各激光点与轨迹线的距离。然后逐段对路面进行强度增强，集合多滤波器集成的策略进行强度变换和去噪，消除距离、点密度、磨损等因素对反射强度值影响，增强路面点云和标线的强度差异。基于增强后的反射强度，采用k均值聚类和连通分支聚类等方法对标线进行分割，并利用归一化图割方法优化强度分割结果。最后利用实线型标线的语义信息和空间分布特征从分割后标线对象中识别实线型交通标线。试验采用四份不同车载激光扫描系统获取的数据用于验证本文方法有效性，实线型标线提取结果的准确率达到95.98%，召回率达到91.87%，综合评价指标F1-Measure值达到95.55%以上。试验结果表明本文方法能够有效增强受扫描距离、路面磨损及点密度分布不均等因素影响的点云强度信息，实现不同车载激光扫描获取的复杂道路环境下实线型交通标线的提取。 相似文献
6.
The existing roadway infrastructures are mostly archived with two-dimensional (2D) drawings that lack the possibility for three-dimensional (3D) interpretation and advanced 3D analysis. The mobile LiDAR system (MLS) is gaining popularity in 3D mapping applications along various types of road corridors. MLS achieves the highest data quality and completeness among the traditional roadway data collection methods. The rural roads in different countries especially in India form a substantial portion of the road network. Therefore the proper maintenance and road safety analysis of rural roads are recommended activity, which could be addressed using detailed 3D road surface information. The absence of raised curb at road boundary, and presence of complexity, heterogeneity and occlusions along the rural roadway settings restrict the use of existing studies for road surface extraction using MLS point cloud data. Therefore considering the above requirement, this research paper proposes a two-stage method. The first stage extract planar ground surfaces which are further used to filter road surface in the second stage. Global properties of road, that is, topology and smoothness and its radiometric response to laser beam of MLS are used in the second stage. MLS point cloud data of rural roadway were used to test the proposed method. The road surface points were accurately extracted without being affected by the absence of raised curb and hanging objects over the road surface, that is, tree canopies and overhead power lines. The quantitative assessment of the proposed method was performed in terms of correctness, completeness and quality, which were 96.3, 94.2, and 90.9%, respectively. 相似文献
7.
Bahman Soheilian Nicolas Paparoditis Didier Boldo 《ISPRS Journal of Photogrammetry and Remote Sensing》2010,65(4):347-359
This paper presents an automatic approach to road marking reconstruction using stereo pairs acquired by a mobile mapping system in a dense urban area. Two types of road markings were studied: zebra crossings (crosswalks) and dashed lines. These two types of road markings consist of strips having known shape and size. These geometric specifications are used to constrain the recognition of strips. In both cases (i.e. zebra crossings and dashed lines), the reconstruction method consists of three main steps. The first step extracts edge points from the left and right images of a stereo pair and computes 3D linked edges using a matching process. The second step comprises a filtering process that uses the known geometric specifications of road marking objects. The goal is to preserve linked edges that can plausibly belong to road markings and to filter others out. The final step uses the remaining linked edges to fit a theoretical model to the data. The method developed has been used for processing a large number of images. Road markings are successfully and precisely reconstructed in dense urban areas under real traffic conditions. 相似文献
8.
9.
In this paper we present an approach for automatic analysis of urban accessibility using 3D point clouds. Our approach is based on range images and it consists in two main steps: urban objects segmentation and curbs detection. Both of them are required for accessibility diagnosis and itinerary planning.Our method automatically segments facades and urban objects using two hypotheses: facades are the highest vertical structures in the scene and objects are bumps on the ground on the range image. The segmentation result is used to build an urban obstacle map. After that, the gradient is computed on the ground range image. Curb candidates are selected using height and geodesic features. Then, nearby curbs are reconnected using Bézier curves. Finally, accessibility is defined based on geometrical features and accessibility standards.Our methodology is tested on two MLS databases from Paris (France) and Enschede (The Netherlands). Our experiments show that our method has good detection rates, is fast and presents few false alarms. Our method outperforms other works reported in the literature on the same databases. 相似文献
10.
为了解决高分辨率遥感影像道路交叉口位置检测与类型识别问题,提出了一种基于可变形部件模型的道路交叉口检测方法。首先,分析了道路交叉口在高分辨率遥感影像上的表征形式;然后,借鉴面向对象的思想,利用可变形部件模型,通过训练和学习其整体和部件组成的空间布局特征获取目标对象模型参数;最后,通过滑动窗口搜索匹配方法获取道路交叉口位置和其对应的类型。由仿真与实验结果可知,此算法不仅能够自动、准确地检测道路交叉口的几何位置,而且能够识别其几何形状类型,可有效提高道路网络拓扑结构构建效率。 相似文献
11.
道路交通标线信息是道路导航地图中必不可少的数据，对于制作精度更高、道路细节信息更加丰富清晰的高精度导航地图具有重要的作用。本文以车载近景立体影像中的道路交通标线信息自动提取为研究目标，针对道路交通标线快速、精确采集的应用需求，提出了基于几何规则的车载近景立体影像道路交通标线自动提取方法。该方法首先分析了道路交通标线的几何特征；其次，构建了基于几何特征的交通标线信息提取规则；最后，以标线种子点为基础，结合前述规则，实现了道路交通标线三维空间信息的自动采集。以南京师范大学的车载移动测量系统拍摄的实际近景立体影像为数据进行了试验，试验结果证明，本文方法相比传统人机交互采集方法，在交通标线特征点采集效率、标线几何相似度等方面有较大的优势，可为高精度导航地图的生产提供一种可借鉴的技术支撑。 相似文献
12.
Accurate 3D road information is important for applications such as road maintenance and virtual 3D modeling. Mobile laser scanning (MLS) is an efficient technique for capturing dense point clouds that can be used to construct detailed road models for large areas. This paper presents a method for extracting and delineating roads from large-scale MLS point clouds. The proposed method partitions MLS point clouds into a set of consecutive “scanning lines”, which each consists of a road cross section. A moving window operator is used to filter out non-ground points line by line, and curb points are detected based on curb patterns. The detected curb points are tracked and refined so that they are both globally consistent and locally similar. To evaluate the validity of the proposed method, experiments were conducted using two types of street-scene point clouds captured by Optech’s Lynx Mobile Mapper System. The completeness, correctness, and quality of the extracted roads are over 94.42%, 91.13%, and 91.3%, respectively, which proves the proposed method is a promising solution for extracting 3D roads from MLS point clouds. 相似文献
13.
车载激光点云道路边界提取的Snake方法 总被引：2，自引：0，他引：2
针对车载激光点云中道路边界提取困难,自动化程度低的问题,提出一种基于离散点Snake的车载激光点云道路边界提取方法。不同于传统基于图像建立Snake,本文直接基于离散点建立Snake模型。先利用伪轨迹点数据,确定初始轮廓位置,参数化不同类型的道路边界初始轮廓;然后基于离散点构建适合多类型道路边界的Snake模型,定义模型内部、外部和约束能量,通过能量函数最小化推动轮廓曲线移动到显著道路边界特征点处,实现不同道路边界的精细提取。本文试验采用3份不同城市场景的车载激光点云数据验证本文方法的有效性,道路边界提取结果的准确率达到97.62%,召回率达到98.04%,F1-Measure值达到97.83%以上,且提取的道路边界结果与软件交互提取的结果有较好的吻合度。试验结果表明,本文方法能够修正噪声、断裂等数据质量对道路边界提取的影响,能够实现各类复杂城市环境中不同形状道路边界的提取,具有较强的稳健性和适用性。 相似文献
14.
Automatic road extraction using high resolution satellite image based on texture progressive analysis and normalized cut method 总被引：1，自引：0，他引：1
J. Senthilnath M. Rajeshwari S. N. Omkar 《Journal of the Indian Society of Remote Sensing》2009,37(3):351-361
In this paper the approach for automatic road extraction for an urban region using structural, spectral and geometric characteristics
of roads has been presented. Roads have been extracted based on two levels: Pre-processing and road extraction methods. Initially,
the image is pre-processed to improve the tolerance by reducing the clutter (that mostly represents the buildings, parking
lots, vegetation regions and other open spaces). The road segments are then extracted using Texture Progressive Analysis (TPA)
and Normalized cut algorithm. The TPA technique uses binary segmentation based on three levels of texture statistical evaluation
to extract road segments where as, Normalized cut method for road extraction is a graph based method that generates optimal
partition of road segments. The performance evaluation (quality measures) for road extraction using TPA and normalized cut
method is compared. Thus the experimental result show that normalized cut method is efficient in extracting road segments
in urban region from high resolution satellite image. 相似文献
15.
首先概要介绍了目前较为流行的读取地理信息数据的开源库GDAL的基础知识,分析了使用GDAL进行导航数据处理的优势。然后,通过对目前导航地图数据处理需求的分析,探讨了如何利用开源库GDAL实现对导航数据的处理。特别针对导航道路外扩线生成的需求,本文分析了其数学原理,提出了利用几何法和缓冲区法两种方法实现导航道路外扩线的生成。经过试验发现,几何法在运算速度上和接边效果上要优于缓冲区法,而缓冲区法对一条很长道路的拟合效果要优于几何法。 相似文献
16.
17.
F. Dell&#x;Acqua P. Gamba G. Lisini 《ISPRS Journal of Photogrammetry and Remote Sensing》2009,64(5):482-489
This paper describes a semi-automatic procedure for cartographic mapping using high resolution SAR and interferometric SAR data. Various two-dimensional features are extracted and combined in order to achieve a basic yet effective recognition of the elements in the scene. Many relevant elements of the landscape are automatically extracted without requiring any deep interaction with the operator. Being based on geometric models assuming regularity of shapes and patterns, the procedure is well suited for detecting man-made features, such as the road network (outside and inside human settlements) and built-up areas. It can be used, however, to extract natural features, focusing on different geometric models. Moreover, extracted elements of the scene can be grouped into higher level ones, such as crossroads, bridges and overpasses, through data fusion at the feature level, because the procedure is characterized by a multi-scale, object-based approach. 相似文献
18.
针对道路高精度地图采集中道路标识线快速分类提取问题,提出了一种根据几何结构特征对道路标识线进行自动匹配提取的方法。首先利用点云生成强度特征图像,并根据点云密度分布特征将强度特征图像划分为多个区域;然后对每个区域进行二值化处理;最后考虑路面标识线缺失情况,设计了一种多约束条件的几何特征语义识别模型,实现了不同标识线类型的分类。对车载移动测量系统获取的多段道路点云数据进行实验,结果表明,该方法的道路标识线提取准确率和识别准确率分别为90.01%和82.83%,总体精度达到86.27%。 相似文献
19.
道路信息在多个应用领域中发挥着基础性的作用。光学遥感影像能够以较高的空间分辨率对目标地物进行精细化解译，可大幅增强地物目标的提取能力。充分利用光学遥感影像丰富的几何纹理信息，进行道路的精确提取，已成为当前遥感学界研究的热点与前沿问题。鉴于此，本文依据近年来大量相关文献，对现有的理论与方法进行了归类与总结，通过分析不同方法采用的道路特征组合，将道路提取方法划分为模板匹配、知识驱动、面向对象和深度学习4类方法，简要介绍了道路提取普适性的评价指标并对部分方法进行了分析与评价；最后对现有光学遥感影像道路提取的发展提出了建议和展望。 相似文献
20.
环境与灾害监测预报小卫星星座(环境一号卫星,HJ-1A/B)自发射以来,在环境监测、灾害评估、土地资源调查等领域发挥了重要的作用。但是HJ-1A/B卫星CCD图像的2级产品(HJ-1 CCD图像)几何精度低,实际应用中需要进行几何精校正。HJ-1 CCD图像具有宽覆盖、大视场角、几何变形复杂的特点,几何精校正难度大。针对该问题,本文提出了一个以Landsat TM全球拼接图像为基准,基于Forstner算子和模板匹配的分层配准方法。该方法使用分层匹配获得的大量高精度且分布均匀的控制点构建Delaunay三角网,有效地解决了HJ-1 CCD图像的几何精校正问题。在配准技术研究的基础上,研发了HJ-1 CCD图像几何精校正系统,系统具有全球HJ-1 CCD图像的自动批量处理能力。实验结果表明,本文提出的几何精校正方法精度高,实现了环境星图像的自动批量处理。 相似文献